DESCRIPTION: The project proposes to test a public health model of screening, preventive INH treatment, and adherence counseling plus medical education of primary care clinicians to enhance their skills and attention to TB control. The investigators will test a behavioral adherence intervention for Latino adolescents with latent disease and a medical education program designed to enhance primary care (community clinic) practitioners' treatment of active and latent TB infection. To extend the proposed model to most community clinic settings, the investigators propose to demonstrate outcome effectiveness as well as cost effectiveness in relation to the costs of failing to control latent TB in this population. Public school adolescents will be screened and 300 PPD positive male and female Latino youth (13-18 years) will be assigned at random to either usual medical treatment, usual medical treatment plus non-directed (attention control) counseling, or medical care plus behavioral adherence counseling. Concurrently participating clinic personnel will receive training in TB control. The primary specific aims are to determine whether behavioral counseling increases clinic attendance and adherence to prescribed INH medication relative to controls, and to determine if training increases professionals' knowledge and practice of TB screening and control treatment. Pill count and reported estimates of adherence will be verified by random urine assays. Repeated measures analyses will be used to assess the effects of professional training. Exploratory analyses will identify correlates of adherence, and cost effectiveness analyses will assess the relative costs of screening and treatment compared to the costs of not controlling TB.